The excitement wasn't limited to the filmed scene, either. Of Newhart's appearance, Parsons told
The Hollywood Reporter, "It was incomprehensible; you can't comprehend what it is you're doing. We've had some great people on this set, but he was the first person that I had that feeling of, 'I can't believe you're real.'"

Newhart's "Big Bang Theory" debut will air Thursday, May 2 at 8 p.m. on CBS.